LONDON — A landmark music venue that has hosted gigs by The Rolling Stones, Sex Pistols, The Clash and Oasis has been saved from the threat of closure as part of a U.K.-wide initiative to protect small and grass roots venues. The 100 Club, located on Oxford Street in London has hosted live music since 1942, but a combination of rent rises and high business taxes have left it struggling to stay open for much of the past decade.